Trait fuel_storage::Storage

pub trait Storage<K, V> where
    V: Clone, {
    type Error;

    fn insert(&mut self, key: &K, value: &V) -> Result<Option<V>, Self::Error>;
    fn remove(&mut self, key: &K) -> Result<Option<V>, Self::Error>;
    fn get<'a>(&'a self, key: &K) -> Result<Option<Cow<'a, V>>, Self::Error>;
    fn contains_key(&self, key: &K) -> Result<bool, Self::Error>;
}

Base map trait for Fuel infrastructure

Generics:

• K: Key that maps to a value
• V: Stored value

Required Associated Types

type Error

Error implementation of the storage functions

Required Methods

fn insert(&mut self, key: &K, value: &V) -> Result<Option<V>, Self::Error>

Append K->V mapping to the storage.

If K was already mappped to a value, return the replaced value as Ok(Some(V)). Return Ok(None) otherwise.

fn remove(&mut self, key: &K) -> Result<Option<V>, Self::Error>

Remove K->V mapping from the storage.

Return Ok(Some(V)) if the value was present. If the key wasn’t found, return Ok(None).

fn get<'a>(&'a self, key: &K) -> Result<Option<Cow<'a, V>>, Self::Error>

Retrieve Cow<V> such as K->V.

fn contains_key(&self, key: &K) -> Result<bool, Self::Error>

Return true if there is a K mapping to a value in the storage.

Implementations on Foreign Types

impl<K, V, S> Storage<K, V> for &mut S where
    V: Clone,
    S: Storage<K, V>, 

type Error = <S as Storage<K, V>>::Error

fn insert(&mut self, key: &K, value: &V) -> Result<Option<V>, S::Error>

fn remove(&mut self, key: &K) -> Result<Option<V>, S::Error>

fn get(&self, key: &K) -> Result<Option<Cow<'_, V>>, S::Error>

fn contains_key(&self, key: &K) -> Result<bool, S::Error>

Implementors